Improvement in valve-motion for steam-engines



. 3 go thutml fitatvfi start ifting HUGH REID, on ST. LOUIS, MISSOURI. Letters Patent No. 83,095, llatetl 0mm 13, 1868.

IMPROVEMENT IN VALVE-MOTION FOR STEAM-ENGINES.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

Be it known that I, HUGH REID, of St. Louis, in the county of St. Louis, and State of Missouri, have made certain new and useful Improvements in Valve Motion for Combination 'Low and High-Pressure Steam- Engines; and I do hereby declare that the following is a full and clear description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The object of my said invention is to add tothe advantages arising from the high steam-pressures used in the ordinary high-pressure engine, the advantages arising from the low back-pressure of the low-pressure engine, by passing the exhaust steam from the highpressure-engine cylinder into the ordinary surface or jet-condenser, except at short intervals of time immediately succeeding the completion of each stroke of the piston, when the exhaust is made either directly or indirectly into the air; and the nature of my invention is therefore in an-almost instantaneous operation of a so-called vacuum-valve, (leading to the condenser) by an arrangement of toggle-joints and operating spring and lever connecting with the rock-shaft operating the cylinder-valves; and further, in the connection of said parts regulating the discharge of steam to thecondenser, of a certain atmospheric valve, which permits the discharge of steam to the air or to the heater.

To enable those skilled herein to make and use my said improvement, I'will proceed to describe the same in its construction and operation, referring to the accompanying Figure 1 as a vertical sectional elevation, and to Figure 2 as a general plan, showing the devices forming my said valve-motion, and their, connection with the ordinary parts of a high-pressure engine,- such as is used on the western rivers of the United States.

A represents the exhaust-pipe, into which the steam passes from the steam-cylinder at each end of stroke.

The valves regulating said exhaust are operated by the rock-shafts B, usually connected by lever and cam with the driving-shaft of the engine. As the action of my said improved valve-motion is closely connected with the action of the exhaust-valves of the steamcylinder, I connect my said valve-motion to the rockshaft B, usually called t-lltl"lllll-Sbl'0k6 rock-shaft.

As heretofore indicated, the exhaust steam is passed, for the greater portion of the stroke, into a condensingvessel, which is not shown in the drawings, and may be of any vform.

To regulate the passage of steam to the condenser, I use the vacuum-valve 0, operating the same from the'rook-shait B, as above indicated.

Immediately upon completion of the "stroke of the piston, l permit the steam to exhaust into the air, (or into the usual steam-heater, and therefrom to the air,)

' thus drawing off the volume of the steam, and thus, to a great extent, preventing the great accumulation of water of condensation in the'condenser which would take place were the steam exhausted into the condenser; and again, I exhaust. said steam into the air, because, at the time of said exhaust-action, theeffective force of the engine .is small, because of the small initial velocity of the piston-and the dead centre position of the crank corresponding to the end-of-stroke position of the piston-rod.

condenser-exhaust, and the consequent reduction of back-pressure may take effect quickly and certainly, the action of the vacuum-valve 0 must be prompt and quick, and similarly, the action of atmospheric valve *must be in prompt correspondence with the action of the vacuum-valve. v I

Tojaccomplish the prompt action of the vacuumva1ve,I connect the rock-shaft B, by its crank, 11, with the forked rod, D. At the forked end, d, hereof, this connects with the toggle-links E by the pins 0. Said pins e have, however, an independent motion (to accommodate the lift of the-valve O) in the slots (1 of said forks (1. One end of the toggle-links E issecured by a hinge-joint to the chamber-top of the valve 0, the other end of said links is connected to the cross- Above said cross-headF, I arrange the spring G about said stem 0, said spring pressing upon a collar, 0, of the stem 0, to raise or lower said stem.

The valve 0, itself, I make of the puppet-form, its disks, 0 and C exhaust steam. From the chamber. 0 the exhaust steam passes to the condenser.

In connection'with the exhaust-pipe A, I arrange the discharge-pipe H, in which is the valve I, opening toward the air. The discharge-pipe H connects with the heater of the usual form, or it may discharge steam directly into the air.

The action of the said parts is now as follows:

Immediately upon completion of the stroke of the piston, the vacuum-valve 0 stands closed. Any moveforces the spring upward, and holds the valve G closed. The steam passes then to the atmospheric valve I, overcoming the air-resistance. In this interval of time the toggle-links .E (by action of the rod D and the rock-shaft) have continued to move toward sageof their vertical position by said links E, the slots cl enable the spring (andthe added steam-pressure upon the valve) to throw the toggle-links over in such wise-as to drop the cross-head "F, and thus open the valve 0. Again, it is plain that owing to thedownward pressure of the spring, the weight of the valve In order, however, that the beneficial actionof thehead F, which slides upon the stem 0 of the valve 0.

being of such areas that a small pressure is exerted to keep the valve open by the ment of the rock-shaft B, which, being transmitted to the toggle-links E, acts upon the spring G, thereby a central vertical position, and immediately upon paspins 6, with the toggle-links E, cross-head F, and spring Gr, combined substantially as set forth.

2. The rock-shaft ]3, in combination with the rod 1), links E, valve-stem 0, and valve 0, substantially as set forth.

The combination of the valve 0, the exhaustpipe A, the discharge-pipe H, and atmospheric valve I, as set forth.

HUGH REID.

\Vitnesses:

GEO. P. HERTHEL, J r., ROBERT BURXs. 

